| 摘要 |
<p>The present invention provides an inexpensive voltage boosting circuit for electronic watches, calculators, etc. which may readily be miniaturized by integrated circuit techniques. The circuit comprises a plurality of boosting units connected in series, each of such units comprising a capacitor having first and second terminals and a first field-effect transistor. The field-effect transistor of a first unit is connected between a terminal of the capacitor and a terminal adapted for connection to one side of a power source so as to connect the capacitor terminal with the power source when the transistor is conductive. The first field-effect transistor of a succeeding unit is connected between the capacitor terminal in the preceeding unit and the capacitor terminal in the succeeding unit so as to provide a current path between the capacitor terminals when the last-mentioned transistor is conductive. Switching means are provided for the first transistor in each said unit, such switching means comprising a second field-effect transistor having a source electrode connected to a second terminal adapted for connection to the power source. A third field-effect transistor is also part of the switching means, such transistor having a source electrode connected to the source electrode of said first-mentioned field-effect transistor and to the first terminal of the capacitor. The drain electrodes of the second and third transistors are connected to the gate electrode of the first transistor and means are provided for applying a pulse signal to the gate electrodes of the second and third transistors. Preferably, the field-effect transistors are of the metal oxide semiconductor type (MOS-FETS).</p> |
